Back in January, we met social-media superstar turned model Cameron Dallas, who drew One Direction–level crowds after he touched down in Milan to attend Calvin Klein Collection's runway show. Just a few short months later and the 21-year-old Vine star and musician has moved from front-row guest to the face of Calvin Klein's newest ad campaign.

Shot by legendary photographer Jack Pierson on a Malibu beach, and starring alongside Stella Lucia, Dallas reps Calvin Klein Jeans Limited Edition's spring collection, a white-heavy lineup of crisp denim staples. "Calvin Klein is such an iconic brand in fashion, so I feel like working with them means you're definitely doing something right," says Dallas. "They bring validation to someone, not only in the fashion community but in someone's career, which is why it was such an honor to work with them."

Dallas cites the iconic Marky Mark ad of 1992 as the ultimate inspiration. "He made me want to wear Calvin. The dude is a stud!" And what was it like frolicking all day on the beach in your underwear with Ms. Lucia, an up-and-comer in the world of modeling? "As far as getting comfortable, everyone had a cool sense of humor, which made it easy to get along with them on set."

For those looking for workout tips or diet pointers to get and maintain a model's toned physique, look elsewhere. Dallas lets Mother Nature do the heavy lifting. "My daily diet consists of basically anything I think looks tasty, whether that's pizza, sushi, burgers, quesadillas. I like everything," he says. "I don't work out or watch what I eat—but I need to start so it doesn't catch up to me."

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